Large-scale die-offs of frogs around the world have prompted scientists to take desperate measures to try to save those they can on Nature at 7 p.m. Sunday.

Masterpiece Classic tells the moving saga of two couples whose lives intertwine in both friendship and tragic misunderstanding in post-World-War-II Britain at 8 p.m. Sunday. Part 1 of 2.

Can you remember when everyone in America was not “Going Green?” Earth Days: American Experience looks back to the dawn and development of the modern environmental movement at 8 p.m. Monday and Thursday.

NOVA takes viewers on a sweeping journey from 1609, when Galileo revealed mankind’s place in the galaxy, to today’s quests to discover new worlds in the infinite universe at 10 p.m. Monday.

Tuesday at 7 p.m., NOVA will look at everything California is doing, from energy conservation to the development of new sources of carbon-free power, to find out how the rest of the country can join their aggressive pursuit of a sustainable energy future.

In Afghanistan, many hundreds of boys are being lured off the streets on the promise of a new life, many unaware that their real fate is to be used for entertainment and sex on Frontline at 8 p.m. Tuesday.

Independent Lens: Dirt! The Movie finds out how industrial farming, mining, and urban development have led us toward cataclysmic droughts, starvation, floods and climate change at 9 p.m. Tuesday.

Through A Dog’s Eyes is about dog trainer Jennifer Arnold and also presents the science that explains the amazing dog/human bond at 7 p.m. Wednesday.

Filmmaker Robert Kenner lifts the veil on our nation’s food industry, exposing the highly mechanized underbelly that has been hidden from the American consumer with the consent of our government’s regulatory agencies on POV: Food, Inc. at 8 p.m. Wednesday.